package main

import (
	"fmt"
)

func main() {
	var n, k, min, max, foo int
	min = 1000
	fmt.Scan(&n, &k)
	for i := 0; i < n; i++ {
		fmt.Scan(&foo)
		if foo > max {
			max = foo
		}
		if foo < min {
			min = foo
		}
	}
	fmt.Println(max - min)
}